SoapUI is a free and open source cross-platform functional testing
The OWASP ZAP core project
Python testing tool for writing better programs
Malicious traffic detection system
Flexible, lightweight multi-language test reporting tool
A modern load testing tool, using Go and JavaScript
Powerful, elegant and flexible test framework for Kotlin
PerfView is a CPU and memory performance-analysis tool
Fortio load testing library, command line tool, advanced echo server
SoloPi Automated Testing Tool
A TCP proxy to simulate network and system conditions for chaos
Scalable open source load testing tool
A Node.js tool to automate end-to-end web testing
Testing for Developers. Toolkit that creates test-cases and data mocks
go test with colors
Visual diffing in CI for user interfaces
Lightweight service virtualization/ API simulation / API mocking tool
Quick and Easy server testing/validation
benchmark tooling that loves you
Test automation made simple
Molecule aids in the development and testing of Ansible roles
Generate HTTP load and plot the results in real-time
Install and run Python applications in isolated environments
Desktop app that helps you craft Gatling load-testing simulations
qooxdoo - Universal JavaScript Framework